These solar cells are used in a lens-based concentrator
system that focuses sunlight on the cells to generate
electricity.

Compound solar cells utilize photo-absorption layers
made from compounds consisting of two or more elements,
such as indium and gallium. The basic structure of this
latest triple-junction compound solar cell uses Sharp's
proprietary technology that enables efficient stacking
of the three photo-absorption layers, with InGaAs
(indium gallium arsenide) as the bottom layer.

To achieve this latest increase in conversion
efficiency, Sharp capitalized on the ability of this
cell to efficiently convert sunlight collected via three
photo-absorption layers into electricity. Sharp also
optimized the spacing between electrodes on the surface
of the concentrator cell and minimized the cell's
electrical resistance.

This latest Sharp research and development efforts were
part of the "R&D on Innovative Solar Cells" project
promoted by Japan's New Energy and Industrial Technology
Development Organization (NEDO), Japan's largest public
management organization for promoting research and
development.

Measurement of the value of 43.5%, which sets a record
for the world?s highest concentrating conversion
efficiency, was confirmed at the Fraunhofer Institute
for Solar Energy Systems (ISE) in Germany.

Because of their high conversion efficiency, compound
solar cells have been used primarily on space
satellites. Sharp's aim for the future is to apply this
latest development success into concentrator
photovoltaic power systems that can efficiently generate
electricity using small-surface-area solar cells and
make them practical for terrestrial use.